What should be true of fossils of the earliest tetrapods?

a) they should show evidence of internal fertilization.

b) they should show evidence of having produced shelled eggs.

c) they should indicate limited adaptation to life on land.

d) they should be transitional forms with the fossils of chondrichthyans that lived at the same time.

e) they should feature the earliest indications of the appearance of jaws.

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

If bacteria are much too small to see, what is one reason why can we see colonies in the petri dishes that have plenty of food to eat after only a few days?

Based on the law of dominance, we would expect percent of the offspring from this cross to have large teeth.